Data Extraction
In the context of two datasets, an initial retrieval was conducted using the search term "knee" within the literature, and the publication date range was restricted to the past five years (2018–2023), resulting in a total of 106,304 articles retrieved. Subsequently, based on inclusion criteria, the selection was further refined to include specific types of literature (randomized controlled trials, systematic reviews, meta-analyses), yielding 24,638 articles. Following the application of inclusion and exclusion criteria to different keywords, a final set of 60 articles was included, comprising 10 in Chinese and 50 in English. The article selection process is illustrated in Fig. 3.
The impact of physical intervention in the ankle region on knee joint related diseases
These results are partially derived from seven randomized controlled trials, involving a total of 380 clinical cases. The included studies primarily focused on interventions involving the foot or ankle joints and examined whether these interventions could have a positive impact on the treatment of knee-related conditions to some extent. Specific experimental research details can be found in Table 3.
Table 3
Improvement of foot and ankle joint morphology and function for knee-related diseases
Study | Time | Region | Age | BMI(kg/m2) | Patient | Knee joint disease category | Main intervention modalities | Intervention | Research results | Effectiveness |
Pain | Function | Perform |
Tse 52 | 2020 | Canada | 26.6± 2.9 | 23.5 ± 2.8 | 40 | KOA | Custom arch insoles | | - | - | KAM /ASEM | The addition of variable rigid arch support to lateral wedge insoles can effectively alter the medial knee joint contact force. |
Hunt25 | 2018 | Canada | 65.4 (9.6) | 27.4 (3.5) | 79 | KOA | Gait correction (bunion correction) training | 16week | WOMAC(pain) | WOMAC(Function) | GS/FPS/KAM | Significant reduction in medial knee joint contact force is achieved when correcting hallux valgus angle reaches 7°. Both intervention groups showed improvements in pain and function. |
Gholami17 | 2022 | Iran | | | 5 | KOA | Individualized gait correction training | Single | | | PKAM | Increased lateral quadriceps strength better coordinates knee joint movement and reduces medial muscle tension, thereby decreasing knee valgus and normalizing lower limb strength. |
Mølgaard40 | 2018 | Denmark | 31.2 ± 10.8 | - | 40 | PFPS | Foot and ankle functional training, foot orthosis | 12week | KOSS(pain 0−100) | KOSS(functional) | KOSS(ADL) | Clinical outcomes after 12 weeks of augmented ankle function training (elastic band ankle inversion and eversion exercises, balance exercises, arch muscle contraction exercises) and foot orthoses (with increased navicular height) are superior to isolated knee joint strength exercises (squats, lunges, elastic band knee extension). |
Wyndow58 | 2018 | Australia | 57 ± 10 | 27 ± 6 | 51 | PFOA | Foot and ankle dorsiflexion test | 5 times | ADR | Fm | FPI | Ankle joint mobilization procedures can address restricted dorsiflexion function in patients. |
Coelho7 | 2021 | Brazil | - | - | 117 | PFPS | Foot and ankle joint release | 1times | NPRS | DKV | DROM | Tibial mobilization at the ankle joint significantly increases dorsiflexion range of motion, promotes knee joint flexion-extension angles, and reduces the risk of knee pain. |
Kim30 | 2022 | Korea | 21.96 ± 2.34 | 22.77 ± 2.95 | 48 | PFPS | Foot and ankle function and strength training | 4week | NPRS(0–10) | AKPS | DVI | Interventions targeting the ankle joint, including tibial joint mobilization and ankle strength training, demonstrate significant therapeutic efficacy in pain control and functional improvement for PFPS patients. |
Note: BMI, Body Mass Idex; NPRS, Numeric Pain Rating Scale; AKPS, Anterior Knee Pain Scale: DVI, Dynamic Valgus Index: FPI, Foot Posture Index FPI; KAM, knee adduction moment; ADL, Activities of Daily Living; PKAM, peak of the knee adduction moment;ASEM, ankle/subtalar eversion moments; FPI, Foot Posture Index; ADR,ankle dorsiflexion range; GS, Gait speed; FPS,Foot progression angle; FM, Foot mobility; DROM, Dorsiflexion ROM; DKV,dynamic knee valgus; KOOS,Knee Injury and Osteoarthritis Outcome Score. |
These studies encompassed diverse geographical regions, including Canada, Iran, Denmark, Australia, Brazil, and South Korea, and involved research subjects spanning various age groups, ranging from young adults to the elderly (21–65 years old). The primary focus of these seven studies revolved around knee-related conditions, namely knee osteoarthritis (KOA), patellofemoral pain syndrome (PFPS), and patellofemoral osteoarthritis (PFOA). The principal intervention strategies included functional training, correction, and mobilization of the foot and ankle joints. Specific intervention methods encompassed custom arch supports, gait correction training, individualized gait correction training, foot and ankle functional training and correction devices, ankle dorsiflexion tests, and ankle joint mobilization procedures, among others. These studies employed a variety of assessment tools to measure the efficacy of the interventions, with the most commonly used including pain assessment metrics such as WOMAC scores, KOSS scores, and NPRS scores. Functional assessment metrics included WOMAC scores, KOSS scores, and AKPS scores. Gait and kinematic evaluations included gait phase deviation, gait velocity, knee varus moment, ankle dorsiflexion range (ADR), and foot posture index.
The duration of interventions varied across different studies, ranging from one session to 12 weeks. This suggests that the treatment of knee-related conditions may require different durations, which may be influenced by factors such as the type of condition, the goals of the intervention, and the specific intervention methods.
Tse et al[52] employed custom arch supports for KOA patients but did not provide specific pain and functional outcome results post-intervention, only demonstrating changes in patients' physical abilities. Hunt et al[25]conducted 16 weeks of gait correction training for KOA, assessing outcomes using WOMAC scores, gait velocity, gait phase deviation, and knee varus moment, among other indicators. Gholami et al[17]similarly targeted KOA patients, employing individualized gait correction training as a physical intervention. Mølgaard et al[40]applied foot and ankle functional training and foot orthosis in the treatment of PFPS patients, with a 12-week intervention duration and KOSS scores used to measure efficacy. Wyndow et al[58]conducted ankle dorsiflexion tests for PFOA patients, evaluating outcomes that included ADR, functional measurements, and foot posture index. Coelho et al[7] studied PFPS patients and utilized ankle joint mobilization as an intervention, albeit with only one session, assessing outcomes using NPRS scores, DKV, and range of motion measures. Kim et al[30]performed a 4-week foot and ankle functional and strength training for PFPS patients, assessing outcomes using NPRS scores, AKPS scores, and functional assessments (DVI).
In summary, these research findings underscore the significance of interventions targeting foot structure, lateral knee muscle strength, foot and ankle function, and ankle joints in the treatment of PFPS. These interventions can reduce pain, improve function, and enhance patients' quality of life. Nevertheless, further research is needed to validate these findings and establish the optimal treatment approaches.
The impact of physical intervention on knee joint related diseasess
This result was partially included in six randomized controlled trial studies, involving a total of 246 clinical case studies. The included research content mainly includes:; Regarding the observation of whether physical intervention at the knee joint can have a positive impact on the treatment of knee joint related diseases to a certain extent, specific experimental research information is shown in Table 4
Table 4
Efficacy of different interventions for knee joint strength and functional recovery in knee-related diseases
Study | Time | Region | Age | BMI(kg/m2) | Patient | Knee joint disease category | Main intervention modalities | Intervention | Research results | Effectiveness |
Pain | Function | Perform |
Harput19 | 2019 | Turkey | 29.5 ± 6.8 | 26.1 ± 3.2 | 48 | ACL-R | QFM alternating centripetal and centrifugal training | 8 weeks | IKDC | OLHDT | MVIC | QFM training, incorporating concentric and eccentric alternating exercises, significantly enhances postoperative leg strength. |
Kaya28 | 2019 | Turkey | 29.35 ± 9.71 | - | 32 | ACL-R | Neuromuscular control training | 12 weeks | QMS | HMS | JRS | Neuromuscular control training strengthens patients' proprioception of the lower limbs and enhances their control over the knee joint. |
Vieira55 | 2020 | Brazil 3 | 25.5 ± 2.8 | 25.7 ± 1.9 | 12 | - | Seated knee extension exercise | 3 times | IET | MT | - | Seated knee extension exercises recruit a greater number of leg muscles and generate more power output. |
Erickson13 | 2019 | United States | 15–40 | - | 60 | ACL-R | Blood Flow Restriction Training (BFR) | 24 weeks | PQS | QROT | KB | Blood flow restriction (BFR) training improves and enhances neuromuscular recruitment capacity in ACL-R patients, thus reinforcing knee joint stability. |
Ferraz 15 | 2018 | Brazil | 60.7 ± 4 | 29.9 ± 3 | 48 | KOA | Low load BFR | 12 weeks | VAS | WOMAC | SF−36 | It alleviates knee joint pain in KOA patients, increases QFM strength, and reduces stress responses to pain. |
Lee36 | 2021 | Korea | 27.2 ± 7.0 | 26.4 ± 3.1 28.5 ± 3.4 | 46 | PFPS | Dynamic, static pulling exercises | 12 weeks | VAS | AKPS | HAT/QAT | Dynamic hamstring stretching and strengthening training demonstrate superior clinical effectiveness in enhancing muscle activation compared to static hamstring stretching and strengthening exercises. |
Note: PQS, peak quadriceps strength: QROTD, quadriceps rate of torque: KB, knee biomechanics: AKPS, anterior knee pain scale; HAT, Hamstring acceleration time; QAT, Quadriceps acceleration time; QMS, Quadriceps muscle strength; HMS, Hamstring muscle strength; JPS: joint position sense; WOMAC, Western Ontario and McMaster Universities Osteoarthritis Index; KOOS, Knee Injury and Osteoarthritis Outcome Score; IKDC, International knee documentation committee; OLHDT, One-Leg Hop for Distance Test; LSI, limb symmetry index; SF-36, Short Form Health Survey; IKDC, International Knee Documentary Committee; MVIC, maximum voluntary isometric strength; IET, Isokinetic exercise Torque; MT, Muscle Thickness.
This paper presents a comprehensive analysis of six studies on rehabilitative interventions for knee joint conditions. These studies were conducted across different countries, including Turkey, Brazil, the United States, and South Korea, and encompassed various types of knee joint conditions such as anterior cruciate ligament reconstruction (ACL-R), KOA, and PFPS. The age range of the study subjects varied widely, spanning from 15 to 60 years. Multiple assessment tools were utilized across these studies to measure the efficacy of interventions, including pain assessment metrics such as VAS, WOMAC, functional assessment metrics like AKPS, SF-36, and muscle strength indicators such as quadriceps femoris (QFM)and QMS. The studies employed different intervention strategies, including neuromuscular control training, blood flow restriction training (BFR), seated knee joint stretching exercises, as well as dynamic and static stretching and strengthening exercises.
Harput et al.'s study[19]: In ACL-R patients, 8 weeks of alternating concentric and eccentric training of the QFM significantly improved postoperative leg strength, as assessed by IKDC, suggesting a critical role for neuromuscular control in ACL-R rehabilitation.
Kaya et al.'s study[28]: Similarly in ACL-R patients, a 12-week neuromuscular control training program resulted in enhanced proprioception in the lower limbs and improved control of the knee joint, emphasizing the pivotal role of neuromuscular control in ACL-R rehabilitation.
Vieira's study[55]: In this research, seated knee joint stretching exercises were administered to patients three times a week. The results demonstrated that this exercise regimen recruited more leg muscles and generated more power, providing a simple yet effective rehabilitation approach for improving knee joint function.
Erickson's study[13]: ACL-R patients underwent 24 weeks of blood flow restriction training (BFR), which enhanced neuromuscular recruitment and improved knee joint stability. BFR training appears to be highly beneficial for the rehabilitation of ACL-R patients.
Ferraz's study[15]: KOA patients, a 12-week low-load blood flow restriction training program was implemented. The results indicated that this training improved pain perception, increased quadriceps muscle strength, and reduced pain-related stress reactions, which holds significant implications for KOA patients' rehabilitation and quality of life improvement.
Lee's study[36]: In patients with PFPS, dynamic and static stretching as well as strengthening exercises were conducted over 12 weeks. The results indicated that dynamic hamstring stretching and strengthening training were superior to static training in improving muscle activation and elasticity, potentially leading to better activation of the posterior chain and muscle recovery.
In summary, these studies highlight the critical role of neuromuscular control training in ACL-R rehabilitation, leading to improved leg strength and knee joint control. BFR training shows significant rehabilitation benefits for ACL-R and KOA patients, enhancing neuromuscular recruitment, stability, and pain reduction. Seated knee joint stretching exercises provide a straightforward and effective rehabilitation approach for increasing leg muscle strength. For PFPS patients, dynamic hamstring stretching and strengthening exercises appear more beneficial than static training, as they can better improve muscle activation and elasticity. These research findings provide valuable insights into knee joint disease rehabilitation, but further research is needed to validate the long-term effectiveness and safety of these interventions. Rehabilitation professionals and patients can choose appropriate intervention measures based on individual circumstances to maximize rehabilitation outcomes.
The impact of physical intervention at the hip joint site on knee joint related diseases
This result was partially included in 5 randomized controlled trial studies, involving a total of 396 clinical case studies. The included research content mainly includes:; Regarding the observation of whether physical intervention at the knee joint can have a positive impact on the treatment of knee joint related diseases to a certain extent, specific experimental research information is shown in Table 5
Table 5
A randomised controlled trial of hip strength strengthening for knee-related disorders
Study | Time | Region | Age | BMI(kg/m2) | Patient | Knee joint disease category | Main intervention modalities | Intervention | Research results | Effectiveness |
Pain | Function | Perform |
Earl-Boehm11 | 2018 | United States | 28.6 ± 6.5 | - | 199 | PFPS | Non-weight bearing training for hip strength and abdominal endurance | 6 weeks | VAS | AKPS | HS/KS | Hip joint strength training and core muscle strength training have the potential to enhance lower limb strength and stability. |
Almeida1 | 2021 | Brazil | 24.9 ± 4.6 | 23.0 ± 3.5 | 52 | PFPS | Hip strength training | 6 weeks | AKPS | NPS | - | Strengthening the hip joint's anterior medial and posterior lateral muscle groups can significantly improve pain and functionality in female PFPS patients. |
Emamvirdi12 | 2019 | Iran | 22.1 ± 5.88 | 18.5 ± 24.9 | 64 | PFPS | Knee valgus control training VCI | 6 weeks | VAS | KVA | HAS/HERS | Knee valgus control guidance training can improve knee joint valgus angle and increase hip joint external rotation and abduction strength. |
Zarei62 | 2019 | Iran 5 | 22.25 ± 3.253.25 | - | 40 | PFPS | Exercise therapy with acupuncture treatment | 4 weeks | mSEBT | NPRS | PPTGM/PPTQL | The combination of exercise therapy and acupuncture therapy yields better rehabilitation outcomes in female PFP patients. |
Motealleh41 | 2020 | Iran | 23.18 ± 4.19 | 21.88 ± 1.83 | 44 | PFPS | Lumbar spine pelvic region massage | | VAS | mSEBT | JPS | Single-session lumbar-pelvic area massage immediately improves the balance and strength of the lower limbs in PFP patients, as well as reduces knee joint pain. |
Note: HAS, hip abductor strength; HERS, external rotators strength; KVA, knee valgus angle; AKPS, Anterior Knee Pain Scale; HS, hip Strength; KS, Knee strength; NPS, numerical pain scale; mSEBT, modified star excursion balance test; NPRS, numerical pain rating score; PPTGM, pressure pain threshold gluteus medius; PPTQL, pressure pain threshold quadratus lumborum; JPS,joint position sense. |
This study presents a comprehensive analysis of five studies from different countries, including the United States, Brazil, and Iran, aimed at exploring the rehabilitative effects of various interventions on PFPS patients. The age and BMI ranges of the study subjects also varied. Different intervention strategies were employed across these studies, including hip joint strength training, patellar lateral tracking control training, exercise therapy combined with acupuncture, and lumbopelvic soft tissue manipulation.
Quantitative metrics for treatment efficacy: The research outcomes delineate several quantitative indicators, such as VAS, AKPS (Andrews-Knee and Patellofemoral System), NPS (Numeric Pain Scale), mSEBT (Modified Star Excursion Balance Test), KVA (Knee Valgus Angle), and HAS/HERS (Hip Abduction Strength/Hip External Rotation Strength). These metrics were used to assess the extent of improvement in patients' pain, function, and physiological parameters. These indicators enable a more objective evaluation of the effectiveness of different treatment modalities.
Earl-Boehm's study[11]: In PFPS patients, a 6-week non-weight-bearing hip joint strength training and abdominal endurance training regimen was conducted. The assessment results indicated that this intervention could enhance lower limb strength and stability. Improvements in VAS and AKPS scores suggested improvements in both pain and function.
Almeida's study[1]: This research involved a 6-week hip joint strength training program for PFPS patients. The results demonstrated that strengthening the hip joint's anterior and medial musculature significantly improved pain and function in female PFPS patients, as evidenced by improvements in AKPS and NPS scores.
Emamvirdi's study[12]: A 6-week patellar lateral tracking control training program was administered to PFPS patients in this study. The results showed that this training could improve the knee joint valgus angle (KVA) and increase hip joint external rotation and abduction strength. Improvements in VAS scores and KVA indicated enhancements in pain relief and knee joint stability.
Zarei's study[62]: In this research, a 4-week combination of exercise therapy and acupuncture was conducted for female PFPS patients. The results revealed that this combined therapy exhibited superior rehabilitative effects. Improvements in mSEBT (Modified Star Excursion Balance Test), NPRS (Numeric Pain Rating Scale), and PPTGM/PPTQL (Pressure Pain Threshold General Measures/Pressure Pain Threshold Quadriceps Lateralis) suggested improvements in balance, pain reduction, and increased pain threshold.
Motealleh's study[41]: This study employed a single session of lumbopelvic soft tissue manipulation for PFPS patients. The results showed that this manipulation immediately improved lower limb balance and strength while alleviating knee joint pain. Improvements in VAS scores, mSEBT, and JPS (Joint Position Sense) confirmed this effect.
In summary, the treatment of PFPS requires a comprehensive consideration of factors such as biomechanics, muscle strength, balance, and individual differences. Different treatment methods can provide assistance in different aspects, but the choice of method should be based on the patient's specific condition. Future research should focus on larger-scale studies, long-term follow-up, and a deeper understanding of individual differences to improve PFPS treatment strategies and enhance patients' quality of life.